研究不同氮肥施用量对黑果枸杞生长及品质的影响,为黑果枸杞人工栽培科学施肥提供理论依据和技术支撑.结果表明:施用氮肥对黑果枸杞生长有显著地促进作用,以施氮肥40 g/株时,株高、茎粗、冠幅和叶面积均较大,表现最优;黑果枸杞叶片叶绿素含量随施氮量的增加而增加,但当施氮量超过60 g/株时,叶绿素含量有下降趋势;黑果枸杞百粒重和单株产量随施氮量的增加呈增加后减趋势,当施氮量为40 g/株或60 g/株时,百粒重和单株产量最大,不同施氮量处理间差异显著.综上所述,适量施用氮肥可促进黑果枸杞植株生长和产量,施用量以40～60 g/株尿素为宜.

树高是树木的重要变量之一,在生长和收获模型中得到了广泛的应用,对生物量和碳储量具有至关重要的影响.该研究基于黑龙江省尚志国有林场局90株迎春5号杨树解析木数据,选择3种常用备选模型进行拟合,考虑可能存在的异方差性,建立树高—胸径模型,采用交叉验证的方法对模型进行独立性检验.结果表明,修正Weibull式具有最优的拟合结果,独立性检验指标表明该模型具有较好的适应性和精度,可以用于实际生产中.

1999年,在黑龙江省尚志市一面坡林场进行了樟子松枯梢病综合防治试验.2003年根据防治试验林标准地的调查结果,经计算得知:防治所带来的经济效益非常显著,同时也说明樟子松枯梢病综合防治技术可以从根本上控制病害的发生与危害.

The Scotch pine standard plots in the shoot blight occurring area of Yimianpo Forest Farm of Sangzhi City, Heilongjiang Province were investigated. The results showed that spores disperse at the beginning of May, and spores dispersing increases with average temperature, relative humidity and rainfall. The initial disease developmental stage is from the middle ten days to the last ten days of June, the peak of this disease from the last ten days of July to the middle ten days of August, and the end of this disease is at the middle ten days of September. Temperature, relative humidity and rainfall have great effect on the happening and developing of this disease fc and temperature plays a crucial role in the time of occurrence and end of the disease. The disease increases with the increasing of time, temperature and raifall within the suitable scope of temperature (20--23 ℃ ) . The multi -variant linear regression forecasting equation (y = 10.6+ 1.241y_(0)+0.288t) was established by stepwise regression analysis, and initial disease index and temperature in last month were selected into the model. This equation could forecast disease index for the current year.